KugelKulture

Question from Maria:

I was reading early on, about Kugelkulture, where the wood (not necessarly chipped ) is deeply dug into the soil and even covered with a lot of soil…..Yes, will use a lot of Nitrogen in the process , but I did understand that is a good method.  So, my question is: why one con’t mix the eucaliptus wood chips with soil and continuously add Nitrogen in different forms?

Answer from Pat:

I had never heard of Kugelkulture or Hugelkulture until you mentioned it but today almost everything can be found on the Internet. I looked there and now I understand and am intrigued. Thank you for bringing this German gardening system to my attention. I have often hiked in forests in rainy areas and seen whole tree trunks rotting with new ones springing out of the top. Glorious rot! During the rotting process the tree trunk would need to take nitrogen from the air but then once rotted, it gives all that nitrogen back and thus the whole forest survives on its own residue. (For others reading your comment, here is an interesting description:http://www.richsoil.com/hugelkultur/.)

Unfortunately in a dry Mediterranean climate, where the temperature is mild year-round and rainfall is sparse and largely limited to the fall and winter months, wood—and especially eucalyptus wood— does not rot rapidly. This is basically why our native soils are so thin and lacking in nitrogen. I had a log in my garden when my husband and I first built our home. It was a huge felled eucalyptus, but it fitted perfectly into our landscape and helped to support a bank. Our daughters and their friends played on it when they were children. That was over fifty years ago. A few parts of that enormous tree trunk are still visible today sixty years after I first saw it and still not completely rotted after this many years. And who knows how many years it had lain on the ground prior to that? At least ten years is my guess. Covering it with soil would not have speeded the process much since the back of the trunk had always been covered in soil.

Kugelkulture is a great idea and is in many ways environmentally sensitive, including sequestration of carbon. But this method of making high garden beds with wood buried inside it is far more practical and workable in a cold climate with rainfall year round than in a dry Mediterranean climate such as ours. If you were to pour on nitrogen, such as sulfate of ammonia, onto the wood to get the effect and also irrigate the mound constantly, then you would be ruining the basic concept. KugelKulture is an environmentally sensitive gardening method which is using the nitrogen in rotted wood to grow plants and also saving carbon from getting into the atmosphere while causing no ground pollution from runoff. The information I read also talks about no need for irrigation, something that would work fine in Germany but would never work in our dry climate and Santa Ana winds. Nonetheless, thanks for bringing it to my attention.